Dubbed a 'bio-spleen', the invention uses magnetic nanobeads coated with a genetically-engineered human blood protein called mannose-binding lectin (MBL). The MBL binds to pathogens and toxins, which can then be "pulled out" with a magnet, the developers wrote in the journal Nature Medicine.

The bio-spleen was developed to treat sepsis, or blood infection, which affects 18 million people in the world every year, with a 30-50 per cent mortality rate. The microbes that cause it are often resistant to antibiotics, and spread fast.